Aerographite is a mesh of opaque black carbon tubes that’s flexible, waterproof, conducts electricity and springs back to its original shape after being squashed.

So what is it good for? Batteries, said Adelung. His Institute for Material Science and the Hamburg University of Technology Institute of Polymers and Composites are testing the material as part of super lightweight lithium ion batteries.

“Our first experiments with lithium ion batteries show we have been able to send quite high currents through the material,” said Adelung.

“This is holy grail that everyone is looking for: a microbattery. This looks very promising.”

Cutting the weight of car batteries, for example, would improve their energy efficiency.

Other potential uses: wearable computing, filtration and insulation.

The German scientists also believe they are close to making something even lighter than aerographite, said Adelung. The new materials under construction in the Hamburg institute “are so lightweight you can’t really weigh them.”